Disc valves

ABSTRACT

A valve assembly having a plurality of coaxial disposed bores, a central one thereof being slightly enlarged in diameter and accommodating a plurality of ring inserts for cooperation with a number of thin disc valve members each carrying an O-ring seal in a rectangular peripheral groove. The valve assembly includes at least two ports communicating with the enlarged interior bore on opposite sides of the annular ring insert, and at least one axial aperture extends through the side walls of the groove of the disc valves to enable release of pressure otherwise existing under the O-ring seal.

This is a division of application Ser. No. 478,628, filed June 12, 1974.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to valve assemblies, and moreparticularly, to a rapid acting, fully balanced valve assembly havingparticularly advantageous O-ring seal carrying valve members.

2. Description of the Prior Art:

Numerous applications presently exist for valves and valve assembliescapable of high capacity, utra-fast slow control of any of variousfluids such as water, oil, gas, air, steam and the like. Such valveassemblies, in order to be economically feasible and commerciallyacceptable, must be capable of rapidly diverting or controlling fluidflow in response to the input of only a slight amount of mechanicalforce, power or energy to move the control stem. In addition, it isoften desirable that the valve assemblies be light weight and minimallycomplex. This, of course, has the inherent advantage of minimizing bothinitial construction costs as well as subsequent maintenance outlayswhile at the same time decreasing unproductive down time of overallsystems incorporating such a valve assembly.

While the prior art, as exemplified by U.S. Pat. Nos. 2,656,144,2,702,049, 3,049,239, 3,191,626, and 3,338,550, is generally cognizantof various valve assemblies capable of both mechanical and electricalactuation and balanced for at least certain fluid flow conditions, thesetypes of valve arrangements have not proven to be fully satisfactory inthat they are typically complex, are prone to valve damage afterrepeated operation, do not hold pressure well in both flow directions,aer incapable of extremely rapid operation, and require many complexparts which are not easily manufactured.

The desirable characteristics of a valve assembly for general use havelong been well known as well as the various undersirable characteristicsand disadvantages exhibited generally by the prior art. Nevertheless,and despite the fact that many new valve designs have been attempted inthe past and are presently being attempted in an effort to solve thesedeficiencies, there has heretofore been unavailable a simple, efficient,and economical valve structure capable of rapidly controllingsubstantial fluid flow situations with ony a minimum of energy input. Inaddition, while attempts have been made in the past to provide valveassemblies with O-ring seals capable of extended use, full realizationof the dynamics of an O-ring seal has hindered valve designers andengineers from developing in the past a valve assembly exhibiting vastlysuperior O-ring seal wear characteristics.

SUMMARY OF THE INVENTION

It is, therefore, an object of the present invention to construct arapid acting, fully balanced, compact valve assembly capable ofcontrolling high pressure stream flows with minimal energy input.

The present invention has a further object in the construction of avalve assembly having an enlarged internal bore accommodating at leastone annular ring for coaction with a disc valve carrying an O-ring sealthereabout.

It is a further object of the present invention to efficiently releasepressure otherwise acting to unseat and damage an O-ring seal disposedabout the periphery of a valve member.

The present invention is summarized in that a valve assembly includes amain body member defining at least first, second, and thirdsubstantially cylindrical bores therein, the first and third bores beingaxially aligned with the second bore and disposed on either side thereofin contiguous relationship, the first and third bores having asubstantially equal diameter which is less than the diameter of thesecond bore; an annular ring having an outer diameter equal to thediameter of the second bore and an inner diameter substantially equal tothe diameter of one of the first and third bores, the ring being fixedlydisposed in fluid-tight relationship in the second bore; first andsecond ports communicating with the second bore on opposite sides of thering; a valve steam extending axially through the first, second andthird bores; and actuating assembly connected with the stem for actuallytransposing the same; and at least three valve discs havingsubstantially equal diameters, two of the discs disposed on the steamfor continuous, sliding cooperation with the first and third bores,respectively, to seal the interior of the valve assembly, and the thirddisc disposed on the stem for selective cooperation with the ring so asto control fluid flow between the first and second ports in response tomovement of the stem by the transposing assembly.

The present invention is materially advantageous over the prior art inthat it is light-weight, compact, includes few parts, may be rapidlyreset, is fully balanced in both flow directions, is capable ofcontrolling or diverting high pressure stream flows with minimal inputenergy, exhibits a high repetition rate without damage, and is capableof extremely rapid operation.

Other objects and advantages of the present invention will becomeapparent from the following description of the preferred embodimentswhen taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view of a preferred embodiment of a valveassembly according to the present invention;

FIG. 2 is a side elevational view of a valve disc of the valve assemblyof FIG. 1;

FIG. 3 is a front elevational view taken along line 3--3 of FIG. 2;

FIG. 4 is a cross-sectional view taken along line 4--4 of FIG. 3;

FIG. 5 is a side elevational view of a modification of the valve disc ofFIG. 2;

FIG. 6 is a front elevational view taken along line 6--6 of FIG. 5;

FIG. 7 is a cross-sectional view taken along line 7--7 of FIG. 6;

FIG. 8 is a partial cross-sectional view of another embodiment of thevalve assembly according to the present invention;

FIG. 9 is a partial sectional view of a further embodiment of the valveassembly according to the present invention; and

FIG. 10 is a modification of the valve assembly of FIG. 9.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIG. 1 there is shown a preferred embodiment of a valveassembly according to the present invention which inlcudes a main casingor housing 12 defining first, second and third bores 14, 16 and 18,respectively, which extend in axial alignment completely therethrough.Bores 14 and 18 are contiguous with the enlarged central bore 16 andmeet at chamfered edges 20 and 22, respectively. The diameter of thecentral bore 16 is greater than that of bores 14 and 18 so as toaccommodate annular rings 24 and 26 which are fixedly disposed influid-tight relationship therein.

Annular rings 24 and 26 are preferably identical and have a generallyU-shaped cross-section with substantially flat outer and innerperipheral surfaces. A rectangular groove 28-30 is formed in the outersurface of rings 24 and 26 for accommodating one or more O-ring seals32-34. Seals 32 and 34 cooperate with the interior side walls of bore 16to establish a fluid-tight relationship between. In addition, theannular rings 24 and 26 are held in a fixed axial position within bore16 by any suitable means such as by accommodating the same within ashallow groove formed in the side wall of the bore.

It is noted at this point that the entire main body section 12 of thevalve assembly of the present invention is preferably formed in sectionsdesigned to be joined at or near the location of the annular rings 24and 26 to facilitate ease in assembling the device. It should also beunderstood that the entire assembly is desinged to be fluid-tight andthat the various sections after being joined, may be held in position byany suitable means such as by a plurality of elongated bolts extendingaxially through the main body member 12.

The inner surface of rings 24 and 26 is outwardly divergent at bothsides thereof so as to more efficiently promote sealing engagement ofthe valve discs, to be further described below, therewith.

A plurality of preferably circular fluid ports 36, 38 and 40 are definedin the walls of the main body 12 in communication with the enlargedcentral bore 16. Port 38 is disposed intermediate the fixed position ofannular rings 24 and 26, while ports 36 and 40 are respectively disposedon opposite sides of the rings from port 38. Any suitable fittings suchas cylindrical extensions 42, 44, and 46 may extend, respectively, fromports 36, 38 and 40 to facilitate interconnection of the valve assemblywith fluid flow lines of the system in which the valve is ultimatelyused. While the fittings 42, 44 and 46 have been illustrated herein asdiscreet cylindrical extensions of the main body 12 it should beappreciated that the same may be integrally formed therewith orotherwise joined as by screw threads as desired. In fact, the entirevalve body assembly may be formed by interconnecting a plurality ofidentical or annular ring 24 and valve disc 56 is spaced from annularring 26. In this position, port 38 is isolated from communication withport 36 but is placed in communication with port 40. An appropriatesolenoid assembly 70 is mounted adjacent bore 18 on main body member 12and coacts with a core 72 attached to stem 50 to effect transpositionthereof to an actuated position whereupon discs 52 and 58 remain sealedwithin bores 14 and 18 and disc 54 is moved away from annular ring 24while disc 56 is moved into sealing engagement within annular ring 26.In this position, port 38 communicates with port 36 and is isolated fromcommunication from port 40.

It can be appreciate from the aforegoing, that the valve assemblyaccording to the present invention may be constructed with minimaldifficulty and includes relatively few parts and virtually no parts ofcomplex shape. Furthermore, in view of the unique nature of the valvediscs 52, 54, 56 and 58 and their direct mounting upon valve stem 50,the overall assembly is extremely lightweight and compact and providesvery rapid flow switchover during operation. Also, it can be appreciatedthat the valve assembly illustrated in FIG. 1 is fully balanced withrespect to flows through any of the ports and in any direction. In otherwords, a pressure stream passing through port 38 will act against theright surface of disc 54 and the left surface of disc 58 with equalinfluence whereupon flow forces which would otherwise cause the shaft 50to be moved to the left or to the right are effectively cancelled.Likewise, if the flow from port 38 through annular ring 26 and outthrough port 40 should become reversed, discs 54 and 58 remain in abalanced condition to cancel any forces which might otherwise move thevalves down. At the same time, positive or negative fluid pressureexisting in the path communicating with port 36 will have an equaleffect on substantially identical T fittings having end sectionsdefining bores 14 and 18.

Disposed coaxially through the interior of the main body member 12 is avalve stem 50 having a diameter which is preferably not greater thanhalf the diameter of the smaller bores 14 and 18. The valve stem 50 maytake the form of a thin rod having a circular cross-section and hasmounted thereon four valve discs 52, 54, 56, and 58. Valve discs 52through 58 are identical in configuration and are fixedly disposed alongthe axial length of stem 50 for cooperation with bore 14, annular ring24, ring 26, and bore 18, respectively. It can be appreciated that inthe embodiment of FIG. 1, the internal diameter of bores 14 and 18 isequal to the internal diameter of annular rings 24 and 26 with valves 52and 58 disposed for continuous, sliding cooperation with end bores 14and 18, and valve discs 54 and 56 disposed for selective cooperationwith annualar rings 24 and 26 as the axial position of valve stem 50 ismoved.

Each of the valve disc members 52 through 58 is in the form of asubstantially flat disc having a rectangular groove 60 formed about theperiphery thereof. Groove 60 is designed to accommodate an O-ring seal62 having a diameter slightly greater than the width of the groove so asto form a snug fit therein. In addition, the side walls of each disc areradially tapered or chamfered so as to meet with the side walls ofgroove 60 as shown.

A pair of washers or dust covers 64 and 66 may be mounted in the ends ofthe main body member 12 adjacent bores 14 and 18 so as to preclude theentry of foreign particles, dust, etc. to the interior of the assembly.One end of valve stem 50 is preferably threaded to receive a nut 66which cooperate with washer 64 to constrain a compression spring 68therebetween. Spring 68 acts to bias the valve stem 50 to a firstpredetermined position, shown in FIG. 1, whereupon the valve disc 54 ispositioned in sealing arrangement within the right surface of disc 52and the left surface of disc 54 such that the stem 50 again remainsbalanced or neutralized against movement. The same conditions hold truewhen the valve simply is moved to its actuated position, i.e., theposition wherein valve stem 50 is transposed to the right, as visualizedin FIG. 1, by the actuation of solenoid 70 in receipt of a controlswitch.

In connection with the embodiment of the valve assembly illustrated inFIG. 1, it is noted that the axial dimension of discs 54 and 56 issubstantially equal to the axial dimension of their respectivecooperating annular rings 24 and 26 such that the discs may be rapidlytransposed from a closed position to an open position upon movement ofthe stem 50. Thus, for the configuration illustrated in FIG. 1, thevalve assembly acts as a flow diverter to direct a fluid stream passingthrough port 38 to either port 36 or port 40. By virtue of itsconstruction and design, the valve assembly according to the presentinvention exhibits an extremely high maximum operating pressuredifferential or MOPD, which is a rating that must be properly evaluatedin system designs where reverse pressure sometimes occures due to ashutdown or other unusual circumstance. In the present invention, theMOPD is the full safe working pressure of the valve. This is due to thefact that the disc seals are all of the O-ring type cooperating with theinterior cylinder walls, and more importantly, that the seal is held intight position by forces that act to close and neutralize as soon as apositive closure takes place. In other words, the valve assembly sealsitself by a small pressure difference due to flow. As explained above,the valve assembly itself is balanced against absolute pressure forces;however, just prior to the time that a disc becomes closed against theinterior of one of the annular rings, a small pressure difference willbe exhibited because of the fluid flowing dynamically therearound.

Because of the above pressure difference due to flow, as the valveapproaches one of its two positions, it tends to quickly become closedwhereupon the O-ring sealed disc is moved within its cylindrical seat toaffect a fluid-tight seal. No mechanical force is required to maintainthe valve member in sealed relationship against its seat, with theresult that the full rating of the valve can be applied to any flowport, whether it be closed or opened or acting as an inlet or outlet.The net result is a very rapidly acting assembly which can divert evenhigh flow rate streams in a matter of milliseconds.

Referring now to FIGS. through 4, one of the discs 52 is illustrated indetail and includes four equally spaced apertures 80 extending axiallythrough the side walls of groove 60 adjacent the bottom of the groove asshown. Since it is desired that the valve assembly of the presentinvention be both rapid acting and positive it is preferred that theO-ring have a diameter slightly larger than the width of the groove soas to make a snug fit therebetween. The axial grooves 80 allow pressureotherwise trapped in the bottom corners of the groove by the O-ring tobe released so as to prevent the seal from becoming damaged duringoperation.

A shown in FIGS. 5 through 7, the axial openings may be in the form ofcircular holes 82 which again extend through the side walls of thegroove and enable pressure otherwise trapped below the O-ring to bereleased. The disc valve design illustrated in details in FIGS. 2through 7 recognizes that space is necessary in the bottom of the groovefor expansion of the O-ring as the same is squeezed or expanded withheat. Furthermore, it recognizes that gas otherwise trapped below theO-ring can expand greatly and extremely rapidly as the valve is movedfrom a closed position to an open position. This has often resulted indislodgment of the O-ring seal or complete destruction thereof and hasproven to be a serious disadvantage in the past. The rectangular grooves80 for the circular holes 82 provided by the present inventioneffectively enable the pressure to be released from below the O-ring topreclude the disadvantages noted above. Of course, while only twoexamples of pressure-releasing apertures are illustrated, namely grooves80 and holes 82, any appropriate perforation or opening may be providedin accordance with the teachings of the present invention so as toprevent excessive pressure from building up behind the O-ring. Since theO-rings are held in the grooves like rubber bands, their inherentelasticity is more than enough to maintain the same in their properposition. The opening or apertures for pressure release should not be solarge, however, so as to leave the O-ring with insufficient sidesupport. On the other hand, the apertures or openings should be at leastlarge enough so as not to clog during normal use.

In use, when one of the discs moves out of the opening defined by itscooperating annular ring, if high pressure fluid or air is enframedunderneath the O-ring seal, it will be free to escape after the disc hasmoved. Since the O-ring also affects a seal with the bottom of therectangular groove about the disc, the axial openings in the groove donot detract from the sealing capability of the disc.

In FIG. 8, there is disclosed a second embodiment of a valve assemblyaccording to the present invention, and parts identical to those in FIG.1 are identically numbered and will not be described again for the sakeof brevity. In the assembly of FIG. 8, a pair of annular rings 124 and126 are substituted for annular rings 24 and 26 in the assembly ofFIG. 1. Since the axial dimension of annular rings 124 and 126 isgreater than the axial dimension of corresponding dics 54 and 56, thevalve assembly will completely shut off flow from port 38 to both ports36 and 40 in the position illustrated. When stem 50 is moved slightly tothe left, as visualized in FIG. 8, disc 54 will remain seated withinannular ring 124, however, disc 56 will move away from annular ring 126to open a fluid passage between ports 38 and 40. Likewise, if stem 50 ismoved slightly to the right, as visualized in FIG. 8, disc 56 willremain sealed while disc 54 will be moved away from annular ring 124 soas to open a flow passage between port 38 and port 36. Again, the valveassembly is balanced for all flows and all of the advantages exhibitedby the apparatus of FIG. 1 are similarly exhibited by the modificationof FIG. 8. In the FIG. 8 embodiment, however, an additional position isavailable to completely cut off fluid flow from port 38 to either ofprots 36 and 40. Thereafter, selective admission of fluid through eitherof ports 36 and 40 can be readily selectively obtained by merely movingstem 50 slightly to the left or to the right.

A further embodiment is illustrated in FIG. 9 in which only a singleannular ring 24 is disposed in bore 16. Stem 50 has mounted thereonthree discs and functions to contol the fluid flow between ports 38 and40 acting as either input or output ports. Again, as in the previouslydescribed embodiments, the valve assembly is balanced for all flows inall directions and requires minimal input power to effect a very rapidtransposition of the fluid flow from an off to an on condition. Amodification of the embodiment of FIG. 9 is illustrated in FIG. 10wherein the port openings 38 and 40 are shifted 180° from their relativepositions as shown in FIG. 9, and the middle disc 54 is slightly shiftedto the left on stem 50. The modification of FIG. 10 is therefore anormally on valve while that of FIG. 9 is normally closed whenconsidered in conjunction with the biasing assembly and solenoidoperator shown in FIG. 1.

From the foregoing it should be appreciated that valve assemblies andparticularly valve discs may be constructed in accordance with thepresent invention for particularly advantageous operation. While thestructure of the assembly is extremely simple, lending to its ease ofmanufacture and maintenance, it exhibits advantages not possessed bytypical valve asemblies presently being used. In particular, itsrapid-acting and compact design is accomplished at the same time withthe capability of changing high presure stream flows with minimal inputpower especially since the system is fully balanced for all flowdirections and possesses only a slight unbalance at the instant justprior to closure because of fluid flow dynamics. The valve is thusparticularly advantageous when used in connection with systems whichmust be fail safe or must always assure a positive seal. The assembly isdirect acting and includes fewer parts than conventional assemblies ofthis general type and is considered to represent a material advance inthe art.

In asmuch as the present invention is subject to many variations,modifications and changes in detail, it is intended that all mattercontained in the foregoing description or shown in the accompanyingdrawing, shall be interpreted as illustrative and not in a limitingsense.

I claim:
 1. A valve comprising a disc member defining a generallyrectangular groove about the periphery thereof, a resilient sealdisposed in said groove in contact with the side walls thereof, saiddisc member further defining at least one aperture extending throughboth side walls of said rectangular groove adjacent the bottom thereofwhereby fluid pressure on both upstream and downstream sides of said dicmember may be released.
 2. The valve as recited in claim 1 wherein saidaperture comprises a circular hole.
 3. The valve as recited in claim 1wherein said aperture comprises a groove.
 4. The valve as recited inclaim 1 wherein said disc member is radially tapered such that the sidewalls thereof meet the side walls of said rectangular groove.
 5. Thevalve as recited in claim 1 further including a valve stem extendingaxially through the center of said disc in fixed relationship therewith.6. The valve as recited in claim 1 wherein said aperture opens bothabove and below said seal in said rectangular groove.
 7. A valvecomprising a disc member defining a flat, cylindrical sealing surfaceabout its periphery, a resilient seal disposed about said sealingsurface, and a plurality of seal holding fingers projecting radiallyoutwardly from said disc on both sides of said sealing surface to definea generally rectangular seal receiving groove, said fingers on each sideof said sealing surface defining axial fluid pressure releasing groovestherebetween.